hardware question

[jekillen]

Hello;
I have built a machine with ASUS M2N32 WS pro motherboard.
It has dual network interface ports that are Marvell interfaces.
I understand that FreeBSD does not yet support Marvell as of
v6.2. I did get a reference to a source for the driver source and
instructions to compile and install. But my short term solution was
to get Intel nics that fit in PCIe lane one slots. As fate would have
it one of the slots is situated too close to some copper vain heat
dissipation attachments, so the second interface card will not
fit in the slot for the obstruction.
So, my question is simple:
Can I use a network interface card made for a PCIe lane one slot
in a PCIe lane 16 slot and expect it to work?

By way of explanation: I need to interfaces because I am using
this machine as a web server and I want one public ip address
assigned to it and one private ip address assigned to it also.
I have all but http and dns blocked from the outside. I use ssh
and ftp to post content to the machine on the inside network.
Thanks, not tearing my hair just yet....
Jeff K